451–460 of 591 posts
I just had a really stupid thought, after finishing reading the article. So, the electron is an elementary particle, right? Compared to the proton, the electron is "simple", yes? Despite this difference in complexity, an electron has a charge of -e and a proton has a charge of +e. They are exactly complementary regarding charge (if I am understanding right, I am not a smart person). my question is... why? why must pr…
Earlier quoted context omitted.
Yes, yes, I also understand this. But why are they in units of 1/3(e). Why are down quarks not -0.398390847895...(e) and up quarks not +0.6234098129034809234...(e). Why do they add up so damn neatly?
when you understand quantum theory correctly, you will realize that particles don't exist by themselves. They are a temporary localization. this means that the number of quarks inside a proton is not actually fixed. when a particle becomes disentangled with the system, that localized it, there's no longer a particle I mentioned this recently, in the context of the laziness in language, leading to the miseducation of…
"particles" are just what we call particular kinds of excitations in quantum fields
doesn't in any way answer, or obviate, or otherwise demystify the question of
why the electric charge associated with one sort of "particle" should be exactly 3x the electric charge associated with another.
So your comment is not only gratuitously rude, it's also either (1) wrong or (2) missing some essential explanation.
I just had a really stupid thought, after finishing reading the article. So, the electron is an elementary particle, right? Compared to the proton, the electron is "simple", yes? Despite this difference in complexity, an electron has a charge of -e and a proton has a charge of +e. They are exactly complementary regarding charge (if I am understanding right, I am not a smart person). my question is... why? why must pr…
So first off: charge is quantized. Glossing over some weird particles (like quarks) which can't exist by themselves an integer multiple of e as their charge. It's been a while since I finished undergrad so my knowledge is rusty, but I don't recall any isolatable particles whose charge wasn't -1e, 0, or 1e. If that's the case, the easiest explanation for why they have the same charge is that if they didn't have opposi…
Earlier quoted context omitted.
The obvious way in which those constants are arbitrary is that the meter is just a random length we compare other lengths to (and the gram is an arbitrary mass we use). So, the precise numbers are only meaningful as part of a system built on these units
"Since 2019 the metre has been defined as the length of the path travelled by light in vacuum during a time interval of 1/299792458 of a second, where the second is defined by a hyperfine transition frequency of caesium." ( https://en.m.wikipedia.org/wiki/Metre ) I wouldn't call it totally random, no. It's really derived from somethings real in this universe. > So, the precise numbers are only meaningful as part of a…
Some of you are talking past each other. The speed of light being exactly the number c is arbitrary, because the choice to use the ephemeris second as the base unit of time (regardless of the precision we get by now using cesium atom “beats”) is arbitrary even though it’s based on something real. That’s just standardizing our arbitrary choice.
The charge of an electron is also effectively arbitrary for the same reason. We can have our units based on whatever real thing we want.
What isn’t arbitrary is that, whatever units we use and whatever number we arrive at for the charge of the electron, it true that the quark charge units are (1/3)e. Thus, as the poster pointed out there is a fundamental difference in asking why it works out that way compared to asking why the speed of light is a particular derived number.
tldr: The poster above is wrong about his claim that it’s like asking “Why is the speed of light…” because he’s comparing a number to a relationship.
Earlier quoted context omitted.
Who says you can't? Who says we don't always use it?
Not sure, but Protons are ~1800x more massive than electrons even though they have the same electric charge, so it seems like they would need 1800x more energy to move them. Power in an electric circuit is Watts, which is current in Amperes times voltage. Amperes are one Coulomb or 6.241509x10^18 electric charges per second flowing through a conductor. So a fixed amount of power (Watts) moves a known amount of charge…
This also is why electric power flows along a wire at the speed of light, while electrons can only travel along a wire at the speed of a snail, or about 1 mm per second
Earlier quoted context omitted.
Are there intermediate [electron,] charge states between + and - in superfluids and/or superconductors? Is there superposition with electron charge states?
The typical model of superconductivity says that electrons in the material pair up to form a quasiparticle -- the "cooper pair" -- with new properties, namely not experiencing resistance. The original quantized charge of the electrons still adds up to the same amount. Unlike protons an neutrons, electrons are considered elementary particles that can't be broken down any further, so their charge can not be "divided" i…
> The fractional quantum Hall effect is more complicated and still considered an open research problem. [2] Its existence relies fundamentally on electron–electron interactions. In 1988, it was proposed that there was quantum Hall effect without Landau levels. [3] This quantum Hall effect is referred to as the quantum anomalous Hall (QAH) effect. There is also a new concept of the quantum spin Hall effect which is an analogue of the quantum Hall effect, where spin currents flow instead of charge currents. [4]
Fractional quantum Hall effect: https://en.wikipedia.org/wiki/Fractional_quantum_Hall_effect :
> The fractional quantum Hall effect (FQHE) is a physical phenomenon in which the Hall conductance of 2-dimensional (2D) electrons shows precisely quantized plateaus at fractional values of e^{2}/h, where e is the electron charge and h is the Planck constant. It is a property of a collective state in which electrons bind magnetic flux lines to make new quasiparticles, and excitations have a fractional elementary charge and possibly also fractional statistics
westurner.github .io/hnlog/#story-38139569 ctrl-f "quantum Hall", "hall effect" :
- "Electrical switching of the edge current chirality in quantum Hall insulators" (2023) https://www.nature.com/articles/s41563-023-01694-y ( https://news.ycombinator.com/item?id=38139569 )
But that's not elementary charge.
"Inside the proton, the ‘most complicated thing you could possibly imagine’" (2024) https://www.quantamagazine.org/inside-the-proton-the-most-co... https://news.ycombinator.com/item?id=39374020 :
> Despite this difference in complexity, an electron has a charge of -e and a proton has a charge of +e. They are exactly complementary regarding charge (if I am understanding right, I am not a smart person).
> my question is... why? why must protons and electrons be perfectly complementary regarding charge? if the proton is this insanely complex thing, by what rule does it end up equaling exactly the opposite charge of an electron? why not a charge of +1.8e, or +3e, or 0.1666e, etc? Certainly it is convenient that a proton and electron complement each other, but what makes that the case?
Earlier quoted context omitted.
I am reading this as "it has to be this way, or the model does not hold", but it does not explain why. What causes it? Consistency of a model cannot be the ultimate reason, right?
> I am reading this as "it has to be this way, or the model does not hold", but it does not explain why. What causes it? Consistency of a model cannot be the ultimate reason, right? Perhaps 'because' if the consistency did not exist then the universe would fail to exist. There was the Big Bang, but we do not know what caused the Big Bang. But the particular Big Bang that started our particular universe may not have b…
Earlier quoted context omitted.
> I am reading this as "it has to be this way, or the model does not hold", but it does not explain why. What causes it? Consistency of a model cannot be the ultimate reason, right? Perhaps 'because' if the consistency did not exist then the universe would fail to exist. There was the Big Bang, but we do not know what caused the Big Bang. But the particular Big Bang that started our particular universe may not have b…
Which leads to the wonderful question: why are there any contingent things? And: why are the contingent things that there are as complex as they are? I don't know of any plausible naturalist explanation besides Many-Worlds. And that supposes for the sake of discussion that Many-Worlds is in fact naturalist.
The void in its infinite time and endless space (the same as neither existing) became bored with itself, and in its attempt to destroy itself, split and created the universe we have now. Full of endless wonders and anomalies and beauty and travesty. All for the amusement of itself as one that remembers the abyssal void.
“The proton is a quantum mechanical object that exists as a haze of probabilities until an experiment forces it to take a concrete form.” I’m getting really tired of hazy probability distributions and waves that only collapse and materialize when observed. I 100% accept that QM is a useful tool to model our current understanding based on increasingly sophisticated observations, but I fundamentally don’t believe that…
"I fundamentally don’t believe that a proton is some shape shifting quantum soup of energy that doesn't form until someone comes around and thinks about it." is the way quantum mechanics is often portrayed in pop sci, but it simply can't be true. Quantum mechanics existed just fine before there was anyone to observe it and think about it.
Earlier quoted context omitted.
> So many significant digits includes a level of self-consistency of the model No, that's incorrect. The specific measurement -the most accurate scientific prediction humans have ever made, the anomalous magnetic moment- is only to 1 in 10 trillion. The magnetic moment (think moment of inertia) is the ratio of force from the magnetic field to the mass of the electron. You put an electron into a magnetic field, and it…
For instance, there is disagreement on if time is quantized, and relatively says time is relative. So at the point we might reimagine the basis of our understanding, two independent measurements of Hz are incomparable. Whatever is out there for us to discover, I'm sure it'll take us all by surprise. I've no doubt you know way more about how we measure these things in practice than I do, but our scientific model and m…
I totally get it, and you aren't wrong, but this is literally the thing it applies to the least. The core thing here is that the obvious assumption about how the universe would work is very (>.1%) wrong, and the purely theoretical quantum math is incredibly, absurdly, amazingly correct.
It's not about measuring some amazingly small thing and having it be amazingly correct. It's about us seeing an incredibly large error in how the universe seems to behave, which QED explained perfectly. It's like the ultraviolet catastrophe or einstein's cross except its billions of times more correct.